<!DOCTYPE html>
<html>

<head>
    <meta charset="utf-8" />
    <title>地狗购物网——网页定位导航效果</title>
    <style>
        * {
            margin: 0;
            padding: 0;
        }

        body {
            font-size: 12px;
            line-height: 1.7;
        }

        li {
            list-style: none;
        }

        #content {
            width: 800px;
            margin: 0 auto;
            padding: 20px;
        }

        #content h1 {
            color: #0088bb;
        }

        #content .item {
            padding: 20px;
            margin-bottom: 20px;
            border: 1px dotted #0088bb;
        }

        #content .item h2 {
            font-size: 16px;
            font-weight: bold;
            border-bottom: 2px solid #0088bb;
            margin-bottom: 10px;
        }

        #content .item li {
            display: inline;
            margin-right: 10px;
        }

        #content .item li a img {
            width: 230px;
            height: 230px;
            border: none;
        }


        /*请补充此处代码，让导航菜单在右侧绝对定位显示*/
        #menu {
            position: fixed;
            z-index: 100;
            top: 30px;
            right: 120px;
            background: #fff;
        }

        #menu ul li a {
            display: block;
            margin: 5px 0;
            font-size: 14px;
            font-weight: bold;
            color: #333;
            width: 80px;
            height: 50px;
            line-height: 50px;
            text-decoration: none;
            text-align: center;
        }

        #menu ul li a:hover,
        #menu ul li a.current {
            color: #fff;
            background: #0088bb;
        }

        /*ie6 hack*/
        * html,
        * html body {
            background-image: url(about:blank);
            background-attachment: fixed;
        }

        * html #menu {
            /*position: fixed;*/
            position: absolute;
            top: expression(((e=document.documentElement.scrollTop)?e:document.body.scrollTop)+100+'px');
        }
    </style>
    <script src="http://libs.baidu.com/jquery/1.10.2/jquery.js"></script>
    <script>

        //滚动条发生滚动时，要获取相应的值。
        $(function () {
            //请补充此处代码，让导航菜单实现在滚动条滚动的时候自动设置焦点
            $(window).scroll(function () {
                var top = $(document).scrollTop();
                var menu = $("#menu");
                var content = $("#content");
                var items = content.find(".item");
                var currentId = "";
                items.each(function () {
                    var m = $(this);
                    var itemTop = m.offset().top;
                    if (top > itemTop - 200) {
                        currentId = "#" + m.attr("id");
                    }
                    else {
                        return;
                    }
                });
                var currentLink = menu.find(".current");
                if (currentId && currentLink.attr("href") != currentId) {
                    currentLink.removeClass('current');
                    menu.find("[href=" + currentId + "]").addClass('current');
                }
            });

            //给相应楼层的a 设置 current，取消其他链接的current
        });
    </script>
</head>

<body>
    <div id="menu">
        <ul>
            <!--运用锚点，实现导航定位。-->
            <li><a href="#item1" class="current">1F 男装</a></li>
            <li><a href="#item2">2F 女装</a></li>
            <li><a href="#item3">3F 美妆</a></li>
            <li><a href="#item4">4F 数码</a></li>
            <li><a href="#item5">5F 母婴</a></li>
        </ul>
    </div>
    <div id="content">
        <h1>地狗购物网</h1>

        <div id="item1" class="item">
            <h2>1F 男装</h2>
            <ul>
                <li><a href="#"><img src="http://img.mukewang.com/53660fce0001111903990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/53660fce0001111903990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/53660fce0001111903990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/53660fce0001111903990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/53660fce0001111903990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/53660fce0001111903990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/53660fce0001111903990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/53660fce0001111903990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/53660fce0001111903990422.jpg" alt="" /></a></li>
            </ul>
        </div>
        <div id="item2" class="item">
            <h2>2F 女装</h2>
            <ul>
                <li><a href="#"><img src="http://img.mukewang.com/5366104c0001e5c403990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/5366104c0001e5c403990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/5366104c0001e5c403990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/5366104c0001e5c403990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/5366104c0001e5c403990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/5366104c0001e5c403990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/5366104c0001e5c403990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/5366104c0001e5c403990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/5366104c0001e5c403990422.jpg" alt="" /></a></li>
            </ul>
        </div>
        <div id="item3" class="item">
            <h2>3F 美妆</h2>
            <ul>
                <li><a href="#"><img src="http://img.mukewang.com/536610820001cf5b03990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610820001cf5b03990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610820001cf5b03990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610820001cf5b03990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610820001cf5b03990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610820001cf5b03990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610820001cf5b03990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610820001cf5b03990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610820001cf5b03990422.jpg" alt="" /></a></li>
            </ul>
        </div>
        <div id="item4" class="item">
            <h2>4F 数码</h2>
            <ul>
                <li><a href="#"><img src="http://img.mukewang.com/536610ac00012df703990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610ac00012df703990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610ac00012df703990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610ac00012df703990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610ac00012df703990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610ac00012df703990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610ac00012df703990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610ac00012df703990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610ac00012df703990422.jpg" alt="" /></a></li>
            </ul>
        </div>
        <div id="item5" class="item">
            <h2>5F 母婴</h2>
            <ul>
                <li><a href="#"><img src="http://img.mukewang.com/536610cd0001f34603990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610cd0001f34603990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610cd0001f34603990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610cd0001f34603990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610cd0001f34603990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610cd0001f34603990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610cd0001f34603990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610cd0001f34603990422.jpg" alt="" /></a></li>
                <li><a href="#"><img src="http://img.mukewang.com/536610cd0001f34603990422.jpg" alt="" /></a></li>
            </ul>
        </div>
    </div>
</body>

</html>